Caster



March 29, 1949. c. R. NALLE 2,465,742

CASTER 3 Sheets-Sheet 1 Filed Feb. 1, 1945 jiwe 02H March 29, 1949. c. R, NALLE 2,465,742

CASTER Filed Feb. 1, 1945 3 Sheets-Sheet 2 March 29, 1949. c. R. NALLE 2,465,742

CASTER Filed Feb. 1, 1945 I 3 She'ets-Sheed 3 Patented Mar. 29, 1949 UNITED STATES PATENT OFFICE CASTER" CharIes'Rl Nall, Philadelphia, Pa.

Application February 1, 1945;"Serial-No. 575, 625

11 Claims. 1

This invention relates to adjustable casters or glides for articles of furniture etc., by. which leveling or steadying of the supported article may be effected to compensate for warpin or other irregularities of the article itself and/ or thefloor or platform on which the article is standing.

The principal object of the present'invention is to provide a simple and efficient form of device, which can be readily applied to the legs of chairs or tables, etc., or tothe bases of cabinets etc. Without necessitating any harmful hammering or pounding on the glide or caster per se to effect installation thereof.

The device of the present invention comprises a simple form of internally threaded socket including a circumferentially pronged base and a central perpendicularly elongated neck; wherein the neck may be initially inserted in a preboring formed in the article of furniture; and wherein the socket, without the glide or caster attached thereto, may be installed and secured in place by a sharp blow directed against the base of the socket, to drive the prongs thereof into the --W00d or other material of which the article is formed.

In the elongated neck is loosely confined a radially expandable and contractible retainer in the form of a sleeve, cap, or nipple which is adapted to attach itself automatically to the stem of the floor-engaging part of the caster structure, when the stem is threaded deeply into the socket, after the latter has been installed.

The retainer is adapted to snap over a head formed on thestem of the floor-engaging element to move freely in the neck of the socket with the stem and maintain the stem in the socket against subsequent accidental removal therefrom during fiiture handling of the article or sliding thereof over the floor, from place to place.

The construction and operation of the device will be more fully disclosed hereinafter, reference being had to the accompanying drawings of which:

Fig. its a vertical sectional view which shows the preferred form of the. device with the socket installed in an article of furniture and the-stem of the glide initially entering the loose retainer within theneck of the socket to hold the stem in" the socket thereafter;

Fig. 2 shows the head of the stem-fullyinserted the retainer;

Fig. 3 shows thethrea'ded stem of the glide backed out of the internal threads in the base'of the socket, with the retainer preventing complete Withdrawal of the stem from the soaked" Fig. 4 is a detail view of the retainer;

Fig. 5 is a sectional plan'view taken on theline 5-=5, Fig. 1;

Figs. 6, Wand 8 are views corresponding'toFigs. 2, s and 4, respectively, but showing a modified form of stem and retainer:

to 'opposite -to' th'at -occupied-byor attached to the Figs. 9, 10, 11 and 12 are views similar to Figs. 1 2, 3- and 4 respectively but showing a still further modified; form of the invention;

Figs. 13, 14 and 15 correspond to Figs. 1, 3 and 4 respectively and illustrate another modified form of the invention; and

16 illustrates a modification of that form of the invention shown in Fig. 14.

Asshown in Figs. 1, 2 and 3, the socket section A of the caster structure of the present invention includes a hollow polygonal cup-like base I, including a bottom plate 2 and integral perpendicular sidewalls 3, 3, which, at the intersections of the adjacentangularl'y disposed parts of the perimeter of the base l are sharply pointed and project perpendicularly tothe plane of the bottom 2 to form prongs 4 for securing the device to the lower end of the leg of a chair or table etc;. or to the underside of the bottom of a cabinet etc.

Within the polygonal base I is housed a similarly shaped internally threaded nut 5, for receiving external threads 6 on the stem 1 of the caster or glide section B of the caster structure C.

The socket section A also includes a hollow ,a'xially elongatedthimble or sleeve 8 which preferably is provided with a closed end 9. The thimble or sleeve 8 is adapted to enter a preboring lo'f ormed-in the article of furniture etc. D with which the caster structure C is to function.

'Ifhe opposite open end of the thimble or sleeve 8is provided with acircumferential, circular or polygonal flange H (see Fig. 5) which is disposed in a plane parallel to the base plate 2 and lies on the upper surface of the nut 5, within the cup likeibase I.

The upper edgesof'the side walls 3, 3 of the base I, intermediate the prongs 4, 4 are provided with tongues l2, IZ'which are bent radially inward over the top of the peripheral flange ll of the thimble 8, to secure the thimble 8, the nut 5,

and the base I, together as a unit, to form the socket section A of the caster structure C.

Loosely mounted in the thimble 8, between the closed end Qthereof and an internal annular shoulder l3 formed by the inner upper surface of the hut 5, th'sock'et section'A is provided with a radiallwexpa'nd'able, inherently contractible retamer E, for securing the stem I of the caster-or giicn'section B in'the socket section A of the caster 'striictu'r "C.

Inf that 'form'of theinvention shown in Figs. 1 to'4inclusive,'the retainer E is'in the'form of'a cylindricallycoiled spring consisting of a plurality of'axial'ly' abutting spiral convolutions I5, I5, of

substantiall -equal diameters. One or both'ends crane retainer E is formed of terminal convolutions lfi ttjlfiz; of-slightly smaller diameter than 17116 00115- l5;

The insrtable'end'of the stem 1, i. e. the'en'd the socket A after the stem of the caster unit B has once been installed in the socket.

The retainer E is loosely confined in the thimble 8 and its axial length is sufficiently greater than the internal diameter of the thimble 8 to keep the retainer from turning crosswise to the axis of the thimble, whereby the axis of the retainer is at all times maintained roughly in alignment with the axis of the thimble.

With the caster unit B entirely separated from and remotely actuated with respect to the socket A, said socket is first installed in the'article D by inserting the closed end of the thimble or sleeve 8 in the boring H], which has been previously provided in the article.

The sleeve or thimble 8 is inserted into the boring l until the tips of the prongs 4 engage the surface of the article surrouding the boring l0, whereupon a sharp blow directed against the base plate 2. in the direction of the axis of the sleeve 8, will drive the prongs A into the article D, until the inturned tongues l2 solidly engage the underside of the article D.

The frusto-conical head I! of the stem 1 of the floor-engaging section or element B is then slipped axially through the internal threads M of the nut 5, after which the threads 6 of the stem 1 are placed in threaded engagement with the threads M of the nut 5. The stem 7 is then rotated and thereby threaded into the nut 5, until the small end of the head ll of said stem engages the small terminal convolution la. at one end of the retainer E.

Continued screwing of the stem 1 into the nut 5 moves the retainer E into the position shown in Fig. 1. Still further turning of the stem 1 in the nut 5 drives the frusto-conical head I! of the stem through the small convolution l5a, causing it to expand radially, while the retainer E is held against the closed end 9 of the thimble 8. The axial movement of the stem 7, by the turning of the stem in the nut 5, moves the head I! up into the retainer E until the small terminal convolution l5a of the retainer spring E snaps over the shoulder formed by the base of the frusto-conical head I! and enters the annular groove l8 formed in the stem under the head I! thereof.

The retainer E is now permanently secured to the stem 1 and, as shown in Fig. 3, backing of the stem 1 out of the nut 5, until the threads 6 of the stem are free of the threads M of the nut 5, will result in the small terminal convolution l5a at the lower end of the retainer E resting upon shoulder I3 formed by the upper side of the nut 5 in the socket A, thereby preventing complete removal of the floor-engaging section B from the socket section A, which frequently takes place when chairs and other articles equipped with adjustable floor-engaging elements are slid or dragged over the floor in a manner to cause counterclockwise rotation of the stem of the floor-engaging element with respect to the threaded portion of the socket firmly secured in the article.

In that form of the invention shown in Figs. 1 to 3 inclusive, the neck N5 of the stem I, from the underside of the head IT to the beginning of the threads 6, is of suflicient length to permit the threads 5 to be backed completely out of the internal threads l4 of the nut 5; whereas, in the modified structure shown in Figs. 6, 7 and 8, the neck lfia is relatively short, whereby the small terminal convolution l5a. at the one end of the retainer El will engage the top surface of the socket nut 5a before the threads 6a of the stem 10. are completely disengaged from the threads l la of the nut 5a.

While the latter structure is practical, it is not as preferable as the structure shown in Figs. 1, 2 and 3, for the reason that there is a tendency, should one attempt to force the stem la in a counter-clockwise direction, for the free end of the terminal convolution l5a. to jamb in the threads Ma of the nut 5a, it'being noted that in this instance the convolutions of the retainer El are wound right handed in accordance with the right hand thread Go of the stem la.

It will be also noted that in the structure shown in Figs. 1-4 inclusive the convolutions l5 of the retainer E are wound in a counter-direction to the threads on the stem and in the nut 5. in order to prevent any jambing of the terminal convolutions of the retainer E in the threads [4 of the nut 5.

In that form of the invention shown in Figs. 9, 10, 11 and 12 the spring-type retainer E and El is replaced by a sleeve-type retainer E2, which is split longitudinally, as indicated at 20, and is adapted to fit snugly around the neck l6b of the stem 1?], between the innermost of the threads 6b on said stem and a shoulder lBb formed in the larger end of the frusto-conical head ll!) of the stem lb. The sleeve-type retainer E2, in this instance, is installed on the stem '8 in substantially the same manner as the spring type of retainer E is installed, as will be obvious by comparison of Figs. 1 and 9, and Figs. 2 and 10.

As shown in Fig. 3 the stem lb is not permitted to be backed completely out of the nut 51) of the socket structure A2, as a result of the lower end 2| of the sleeve E2 engaging the upper surface shoulder-forming surface lSb of the nut 52), while the upper end of the sleeve E2 engages the shoulder l8b on the head ill) of the stem lb.

In that form of the invention shown in Figs. 13, 14, 15 and 16 the spring and sleeve types of retainers E, El and E2 are replaced by a cup-type of retainer, shown in Fig. 15. The cup-retainer E3 comprises a crown 23 which is adapted to fit over the small end l9c of the frusto-conical head He of the stem 10, and is provided with a skirt 24 having one or more longitudinal slits 25, to permit the retainer to expand and contract radially. The open end of the cup retainer E3 is provided with an inturned flange 26 which is adapted to snap under the shoulder l8c formed by the larger end of the frusto-conical head He of said stem.

As shown in Figs. 13 and 14 the stem 1c is provided with a short neck l6c which prevents the threads 66 of the stem 'lc from being backed completely out of the threads Me of the nut 50; while the structure shown in Fig. 16 provides the long neck lBd by which complete removal of the threads 6d of the stem 111 from the threads l4d of the nut 5d is permitted.

I claim:

1. A caster structure comprising a hollow socket having an open end, internal threads in said open end, a floor engaging element including a threaded stem for entering said open end to cooperate with said internal threads, an annular shoulder on said stem, and a radially expandable and eontractible retainer loosely confined in said socket internally beyond said internal threads said retainer comprising a coiled spring including a plurality of convolutions of one diameter and a terminal convolution of relatively smaller diameter for gripping said stem under said shoulder to cause said retainer to move with said stem in said socket and to prevent withdrawal of said stem from said socket.

2. A caster structure comprising a hollow cuplike base including flat angularly related side walls, a correspondingly flat sided nut seated in said base, a hollow thimble open at one end and axially aligned with said nut and said base, a flange on said thimble resting on said nut, and ears forming part of said side walls bent inwardly over said flange and securing said base nut and thimble together as a unit.

3. A caster structure comprising a hollow cuplike base including flat angularly related side walls, a correspondingly flat sided nut seated in said base, a hollow thimble open at one end and axially aligned with said nut and said base, a flange on said thimble resting on said nut, ears forming part of said side walls bent inwardly over said flange and securing said base nut and thimble together as a unit, and prongs formed on said side walls intermediate said ears for securing said unit to an article to be supported by said caster structure.

4. A caster structure comprising a hollow cuplike base including flat angularly related side walls, a correspondingly flat sided nut seated in said base, a hollow thimble open at one end and axially aligned with said nut and said base, a flange on said thimble resting on said nut, ears forming part of said side walls bent inwardly over said flange and securing said base nut and thimble together as a unit, prongs formed on said side walls intermediate said ears for securing said unit to an article to be supported by said caster structure, and a floor engaging unit comprising a stem threaded through said nut into said hollow thimble.

5. A caster structure comprising a hollow cuplike base including flat angularly related side walls, a correspondingly flat sided nut seated in said base, a hollow thimble open at one end and axially aligned with said nut and said base, a flange on said thimble resting on said nut, ears forming part of said side walls bent inwardly over said flange and securing said base nut and thimble together as a unit, prongs formed on said side walls intermediate said ears for securing said unit to an article to be supported by said caster structure, a floor engaging unit comprising a stem threaded through said nut into said hollow thimble, and means loosely confined in said thimble beyond said nut and secured to said stem to prevent removal of said stem completely from said nut.

6. A caster assembly comprising a hollow socket having an open end, a floor engaging element including a stem of substantially smaller diameter than said hollow socket and adapted to move axially in said socket, an abutment forming the base of said hollow socket, a locking member adapted to slide axially in said socket.

a flange adapted to close the open end of the socket after said locking member is inserted in the socket, said flange having a hole therein adapted to permit passage of the stem but to prevent withdrawal of the locking member whereby the locking member may be secured to the stem by pressing the locking member between the stem and the abutment of the socket after the flange is permanently secured to the socket.

'7. A caster assembly in accordance with claim 6 in which there is an annular shoulder on the stem adapted to engage the locking member.

8. A caster assembly in accordance with claim 6 in which the locking member comprises a radially distendable element adapted to enclose the stem and having a distended diameter less than the bore of the socket.

9. The method of assembling a caster having a hollow socket, and a stem adapted to rotate in said socket which comprises; inserting a locking member in the socket, permanently securing a flange member at the open end of said socket to prevent removal of the locking member, inserting the stem of a floor engaging element through a hole in said flange, and compressing the locking member between said stem and the base of the socket to permanently engage the locking member and the stem thereby preventin withdrawal of the locking member.

10. An adjustable support for furniture and the like comprising a floor engaging element, a threaded stem attached to said element, the threads on said stem terminating below the upper extremity of the stem, an annular retaining shoulder on the upper extremity of the stem, said shoulder being in spaced axial relation to the terminus of the threads, an annular groove on the stem between the shoulder and the terminus of the thread, the diameter of said groove being less than the root diameter of the threads on the stem, an internally threaded member non-rotatably mounted on said article of furniture, and a radially expandable and contractible retainer adapted to fit over said shoulder so that when the stem is threaded through the bore and the retainer installed over the shoulder, the axial distance between the terminus of the threads on the stem and the retainer is sufficient to permit free turning of the stem in the threaded bore when the threads are completely disengaged whereby the retainer prevents withdrawal of the stem from the bore.

11. Structure in accordance with claim 10, in which, the retainer comprises a coil spring including a plurality of convolutions of one diameter and a terminal convolution of relatively smaller diameter for gripping the stem under the shoulder.

CHARLES R. NALLE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 9,733 Wade May 17, 1853 357,340 Scofield Feb. 8, 1887 452,940 Patterson May 26, 1891 867,943 Boles Oct. 15, 1907 1,232,688 Johnson July 10, 1917 2,254,973 Nalle Sept. 2, 1941 2,385,154 Nalle Sept. 18, 1945 

